Componentize expire_history_backend.{cc,h}

Componentize expire_history_backend.{cc,h}

Move expire_history_backend.{cc,h} into //components/history/core/browser
and update .gyp and .gn files.

Remove some obsolete code in expire_history_backend_unittest.cc file.

BUG=370850
R=droger@google.com

Committed: https://crrev.com/2e7702cc2f8385eb3765552601bb82b99584b836
Cr-Commit-Position: refs/heads/master@{#312929}

[droger, 2015-01-22 16:25:51]

droger@chromium.org changed reviewers:
+ droger@chromium.org

[droger, 2015-01-22 16:25:52]

lgtm

[droger, 2015-01-22 16:26:08]

droger@chromium.org changed reviewers:
- droger@google.com

[sdefresne, 2015-01-22 17:53:41]

The CQ bit was checked by sdefresne@chromium.org

[commit-bot: I haz the power, 2015-01-22 17:55:01]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/870593003/20001

[commit-bot: I haz the power, 2015-01-22 18:49:43]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2015-01-22 18:49:44]

Try jobs failed on following builders:
  linux_gpu on tryserver.chromium.gpu
(http://build.chromium.org/p/tryserver.chromium.gpu/builders/linux_gpu/builds/...)
  linux_gpu_triggered_tests on tryserver.chromium.gpu
(http://build.chromium.org/p/tryserver.chromium.gpu/builders/linux_gpu_trigger...)

Try jobs failed on following builders:
  linux_gpu_triggered_tests on tryserver.chromium.gpu
(http://build.chromium.org/p/tryserver.chromium.gpu/builders/linux_gpu_trigger...)

[sdefresne, 2015-01-23 10:11:35]

The CQ bit was checked by sdefresne@chromium.org

[commit-bot: I haz the power, 2015-01-23 10:12:32]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/870593003/20001

[commit-bot: I haz the power, 2015-01-23 10:12:50]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2015-01-23 10:12:51]

Try jobs failed on following builders:
  linux_gpu on tryserver.chromium.gpu
(http://build.chromium.org/p/tryserver.chromium.gpu/builders/linux_gpu/builds/...)
  linux_gpu_triggered_tests on tryserver.chromium.gpu
(http://build.chromium.org/p/tryserver.chromium.gpu/builders/linux_gpu_trigger...)

[sdefresne, 2015-01-23 21:13:47]

The CQ bit was checked by sdefresne@chromium.org

[commit-bot: I haz the power, 2015-01-23 21:14:00]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/870593003/20001

[commit-bot: I haz the power, 2015-01-23 21:15:33]

Committed patchset #2 (id:20001)

[commit-bot: I haz the power, 2015-01-23 21:16:30]

Patchset 2 (id:??) landed as
https://crrev.com/2e7702cc2f8385eb3765552601bb82b99584b836
Cr-Commit-Position: refs/heads/master@{#312929}